Triclosan Impairs Heart and Skeletal Muscle Contractility

NIEHS grantees report that triclosan hinders muscle contractions at a cellular level and also causes muscle problems in fish and mice. Triclosan is an antibacterial agent widely used in personal-care products such as hand soap and toothpaste, and it has been detected in waterways and fish. This new study provides evidence of the chemical’s potentially negative effects on human and environmental health and also reveals a mechanism for these effects.

The researchers evaluated the effects of triclosan on muscle cells. The triclosan interrupted normal communication between two proteins that function as calcium channels, causing skeletal and cardiac muscles to fail.

In animal studies, anesthetized mice had up to a 25-percent reduction in heart function measures within 20 minutes of exposure to the chemical. Mice given a single dose of triclosan showed an 18-percent reduction in grip strength for up to 60 minutes. The investigators also studied the effects of triclosan exposure on fathead minnows, a model organism used to study the effects of aquatic pollutants. Minnows exposed to triclosan in the water for seven days showed significantly reduced swimming activity compared to controls.